Table I.

Comparison of Various Types of Equivalence Testing

Characteristics	Bioequivalence (Generic drug products)		Biosimilarity (biosimilar drug products)
	In vitro BE testing	In vivo BE testing	Analytical	PK/Clinical
Fundamental assumption	Yesa	Yesb	No	No
Log-data	No	Yes	No	No
Primary focus	Mean	Mean	Mean	Mean
Variability	<10%	20–30%	Vary	40–50%
Criterion	(90, 111%)	(80, 125%)	EAC=± 1.5 * σ R	SABE?c
Analysis	Profile/non-profile	Hypothesis/CI	Hypothesis/CI	Hypothesis/CI

^aDrug release/delivery is predictive of drug absorption

^bDrug absorption is predictive of clinical outcomes

^cSABE is proposed criterion by the FDA for highly variable drug products (i.e., intra-subject CV is greater than 30%) Haidar et al. (11)